German Duchy of Brunswick.

So here we have the German notgeld, pfenning of Braunschweig Federal State, nominal - 5. Mint: Nuremberg, Germany.

The Duchy of Brunswick was a historical German state. Its capital was the city of Braunschweig. It was established as the successor state of the Principality of Brunswick-Wolfenbüttel by the Congress of Vienna in 1814-15. In the course of the 19th-century history of Germany, the duchy was part of the German Confederation, the North German Confederation and from 1871 the German Empire.

By a law of 1879, the Duchy of Brunswick established a temporary council of regency to take over at the Duke's death. With William's death in 1884, the Wolfenbüttel line came to an end. The Duke of Cumberland then proclaimed himself Ernest Augustus, Duke of Brunswick. However, since he still claimed to be the rightful King of Hanover, the Federal Council ruled that he would violate the peace of the German Empire if he succeeded to Brunswick.

The need for a Regent ended in 1913. The Duke of Cumberland's eldest son having died in 1912, the elderly Duke renounced Brunswick in favor of his youngest son, Ernest Augustus, who married Emperor Wilhelm II's daughter, swore allegiance to the German Empire and renounced all claims to Hanover. Accordingly, he was allowed to ascend the throne of the Duchy in November 1913.

In the midst of the German revolutions of 1918, the Duke had to abdicate, and the Free State of Brunswick was founded as a member state of the Weimar Republic.